Explanation: Spread spectrum communication is a technique that intentionally spreads the transmitted signal over a much wider bandwidth than is strictly necessary to transmit the information. One primary method of spread spectrum is Frequency Hopping Spread Spectrum (FHSS), where the RF carrier frequency rapidly changes, or "hops," according to a pseudorandom, predetermined sequence over a wide range of frequencies. This characteristic directly matches the description provided in the question. In contrast: * **Amplitude compandored single sideband (ACSSB)** is a narrowband voice communication method designed for efficient spectrum use, not wide bandwidth, and uses a relatively fixed carrier frequency. * **SITOR (Simplex Teletype Over Radio)** is a data communication mode that typically uses narrow-bandwidth FSK (Frequency Shift Keying) with a fixed carrier. * **Time-domain frequency modulation** is not a standard, recognized communication system that fits the description. Frequency modulation (FM) varies the instantaneous frequency according to the information, but "time-domain frequency modulation" doesn't describe a wide-bandwidth system with a predetermined hopping sequence.